arXiv:1203.1458 · Physical Review A

Macroscopic superposition and entanglement for displaced thermal fields induced by a single atom

Shi‐Biao Zheng

Published Mar 30, 2007• 18 citations

Abstract

We show that a cavity field can evolve from an initial displaced mixed thermal state to a macroscopic superpositions of displaced thermal states via resonant interaction with a two-level atom. As a macroscopic system (meter) is really in a mixed state before coupling with the microscopic system at some temperature, our result is important for studying the quantum measurement problem and decoherence under real conditions. For the two-mode case, entanglement of displaced thermal states between the modes can be obtained.

DOI: 10.1103/physreva.75.032114

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